The present invention relates to a fuel cell vehicle.
1. Field of the Invention
Priority is claimed on Japanese Patent Applications No. 2005-200631, No. 2005-200632, and No. 2005-200633, No. 2005-200634, No. 2005-200635, and No. 2005-200636 filed Jul. 8, 2005, and Japanese Patent Application No. 2005-353358 filed Dec. 7, 2005, the contents of which are incorporated herein by reference.
2. Description of Related Art
In a fuel cell vehicle, a fuel cell stack is formed by stacking a plurality of unit fuel cells, and the fuel cell stack is mounted below a floor panel. In this type of fuel cell vehicle, it has been proposed to attach the fuel cell stack to a sub-frame, and join this sub-frame to the vehicle body skeleton portion, such as side frames of the vehicle, from the vehicle body bottom (see, for example, Japanese Unexamined Patent Application, First Publication No. 2003-182624).
Also, there is known a fuel cell vehicle in which a hydrogen sensor is disposed on the inside upper portion of a center tunnel formed in the bottom of a floor panel, and a silencer of the air supply piping to the fuel cell is disposed below the hydrogen sensor (see, for example, Japanese Unexamined Patent Application, First Publication No. 2003-252252).
However, in the case of such a conventional fuel cell vehicle, the fuel cell stack is disposed under the floor panel over a wide area in the vehicle width direction, leading to problems such as a rise in the overall height of the floor panel and cramping of the seating space of the occupants.
Also, stacking the unit fuel cells in the vehicle body longitudinal direction has been investigated in such a fuel cell vehicle. However, in this case reliably protecting the fuel cell stack against a load applied from a side of the vehicle perpendicular to the stacking direction of the fuel cell stack becomes an issue. Similarly to the fuel cell stack, it is also an issue to dispose in the vehicle auxiliary components of the fuel cell such as a heater for cold starting and a voltage converter so as to reliably protect them against loads applied from outside the vehicle.
Moreover, while measures for endurance have been implemented such as housing the hydrogen sensor in a hydrogen-permeable case that prevents water, mud or the like from splashing onto the hydrogen sensor while allowing natural ventilation of the fuel cell under the floor panel, improvements are sought for cost reduction.
In addition, the aforementioned related art has routed under the floor panel both a high voltage line that extends from the fuel cell stack to high voltage components such as the drive motor of the vehicle, and a low voltage line that extends to low voltage components such as solenoid valves and lamplights. Since such an arrangement raises the possibility of noise from the high voltage line influencing the low voltage line, improvements have been sought in that regard.
Also, the center console that forms the center tunnel abuts the dash lower positioned between the vehicle cabin and the motor room to the front thereof to increase rigidity of the vehicle body and simplify the structure thereof. In this case, because the inside of the center tunnel and the inside of the motor room are continuous, it becomes necessary to dispose a hydrogen sensor in the motor room to detect hydrogen that flows into the motor room via the center tunnel in addition to disposing a hydrogen sensor on the inside upper portion of the center tunnel to detect hydrogen below the floor panel. Improvements in this regard are therefore also sought to reduce the cost of parts.
The aforementioned art inhibits effects on the hydrogen sensor due to water, mud or the like splashed up from a road surface. However, in addition to the hydrogen sensor, it would be preferable to also inhibit the effect due to such splashing from the road surface onto the hydrogen system components and electrical system components. By doing so, the measures for endurance for such components could be scaled down to achieve a cost reduction.
Meanwhile, a constitution has been proposed of mounting the fuel cell stack and the components thereof on a sub-frame and then attaching this sub-frame to the bottom of the floor panel of the vehicle. However, even for such a constitution it is desired to be able to reduce the measures for endurance for the hydrogen system components and electrical system components.